After a couple of candidate swells so far this season not quite making their mark for contest at Padang Padang we thought we’d share a little of our process in making the call, particularly with regards to wave size and power and explain why this one fell short of competition standard, despite some amazing looking waves.

We love the Rip Curl Padang Padang comp. It’s a special break, coming into it’s own just a few times a year when the size, power and direction of a swell shifts proceedings up the reef to a section that, in the right conditions, delivers a wave to test the worlds finest barrel riders. With such specific requirements and such a long waiting period we’re tested as forecasters to a degree that even a WCT event can’t match.

Bali’s reputation is a result of it’s perfect exposure to Southern Hemisphere swell, coupled with a latitude approaching almost equatorial. Given that long travel distance swells arrive with power, but crucially refined and organised with long peak periods, losing height as they propagate from the original storm. Compared to Fiji or Tahiti, equally exposed to roaring 40′s swell but which sit around 10 degrees further south, that extra 500 or so miles is the difference on the largest swells between the sort of waves we see at Chopes or Cloudbreak and those at G-Land, the Mentawais or on the Bukit. Arguing which are better is pointless, but there’s little doubt which get biggest.

But analysing years of records to identify (from photos, videos and local reports) the very best Padang sessions we can see that for it to move from being a typical Indo reef break to something special it needs a taste of this raw power typical of more exposed Southern ocean locations. We’ve run 15 years of forecast swell records and looked at the typical face heights you might expect on an exposed reef to get some idea of exactly what sort of swell can hit Padang with the most power:

While Indo is regularly getting hit by swells in the 17-19 second period range, the peak power here is really most likely to be delivered by swell in the 10-12ft @ 15-16 second range. Given that swell height decays in a predictable fashion as it radiates away from the storm that creates it we can start to get an idea of what sort of size and distance of storm we’re looking at. While Indo is renowned for groomed long period swell and can have meaningful waves from 19 second plus period swells (which can originate West of the Cape of Good Hope) for a swell to hit Padang in this 10-12ft range we’re typically going to be looking at something a little closer to home. Looking at a storm in the upper end of the likely southern ocean range we’re talking about perhaps a 40ft sea at origin (a purple blob on the MSW swell chart) which puts the range for that 10ft swell on the reef at a rough 3000 nautical miles. Move the storm a little closer, perhaps 2500nm and you can get away with a 35ft sea for a similar size.

Direction is also key, the reef at Padang Padang lies in shelter from swell from the South. Like any good point break swell refracts around the headland onto the reef with a loss of size very much dependent on direction. Our records show little of note on swells south of about 208-210 degrees with the range then moving all the way up to around 222 degrees – giving us an effective window to futher understand where exactly we need to be storm spotting. The more northerly the better the power of any swell translates to the reef, however the less likely the ocean is to fire up seas at the intensity needed in the range we’re talking about (with 2011 something of an exception to this). The further south we look the more likely we are to see storms of the power we want in the range we need, but that angle clips a lot of power from the reef.

Boiling all this down and the area of the chart we need to be keeping an eye on to find that perfect Padang swell is perhaps smaller than you might expect, defined below by the two swell window limits at 208 and 222 degrees, and the circles which give an idea of the size required at that distance to give the sort of conditions we need:

2005 was a benchmark swell for Padang Padang. Describing the final surf photographer Dustin Humphrey said “In my eight years of shooting the place that was by far the heaviest back side barrel I have seen out there”. As you can see from the chart above the swell sat right in the 30-35ft window with peak seas right in that range. Arriving on the beach at a model hindcast 11ft@15 seconds it’s right at the very top end of swells we’ve been able to find in our records. This size equates to size on the reef, but it also shifts the consistency of waves in the required size up which is another crucial aspect for the one day competition format.

2009 was another classic for the competition, with locals describing it ‘as good as it gets’ and solid double overhead waves on the reef. You can see the swell sits a little further from Bali, just on the edge of the 35ft zone and with seas in this range which meant it arrived in Bali a foot shy of the 2005 swell, although that area of fetch north of the 222 line meant the overall direction of the swell came in quite a bit further north than in 2005.

2011 was something of an anomaly, sitting further north still than most of the historic swell record. With a long fetch this swell saw peak seas in the 45ft range at one stage further west and on arrival in Bali the hindcast record suggests 10ft@19 seconds from an extremely northerly 225 degrees. The height suffered just a foot on 2005 from the distance at which the storm peaked, but assisted by the duration of fetch and that peak size it was very much in the range. The peak period was exceptional as a result of this distance and it’s extra time in development.

Fast forward to this year and we’ve seen our second ‘candidate swell’ of the waiting period so far hit the reef this Wednesday and Thursday. With model readings always putting it a little shy of where we want to be for competition the chart above really explains at a glance why this is the case. The storm has that 35ft sea we’ve seen create competition conditions before, but lies too far out to bring that size to the beach. Hitting Bali in the 7-8ft@16 seconds range we saw a great warmup session for the event competitors, but very little onto contest range and certainly not the consistency we need.